WO2020134160A1

WO2020134160A1 - Fuel cell metal bipolar plate

Info

Publication number: WO2020134160A1
Application number: PCT/CN2019/103931
Authority: WO
Inventors: 高勇; 郑勤勇
Original assignee: 上海恒劲动力科技有限公司
Priority date: 2018-12-29
Filing date: 2019-09-02
Publication date: 2020-07-02
Also published as: JP7218877B2; CN111384411B; CN113611888A; EP3748750A1; CN113611888B; JP2021536116A; US20210313592A1; EP3748750A4; CN111384411A

Abstract

A fuel cell metal bipolar plate, comprising a cathode plate (1) and anode plate (3) that are formed by stamping a single-layer metal sheet. A plurality of grooves formed by stamping a front surface of the cathode plate (1) form an oxidant flow channel (16), and protruding parts of the edges of said grooves form oxidant flow channel walls; a plurality of grooves formed by stamping a front surface of the anode plate (3) form a fuel flow channel (18), and protruding parts between the grooves form fuel flow channel walls; grooves are formed on back surfaces of the protruding parts of the front surfaces of the anode plate (3) and the cathode plate (1), while groove portions on the front surfaces form ridges on back surfaces. The cathode plate (1) and the anode plate (3) are closely assembled back-to-back, and the grooves and ridges on the back surfaces are coupled to form a groove-to-groove or groove-to-ridge coolant flow channel (17). The bipolar plate has a compact and ultra-thin structure, has good conductivity, is easy process, is low-cost, has a stable structure, and has excellent sealing performance.

Description

Fuel cell metal bipolar plate

Technical field

The invention relates to a fuel cell, in particular to a fuel cell metal bipolar plate.

Background technique

A fuel cell is a device that directly converts the chemical energy of hydrogen and oxygen into electrical energy through an electrode reaction. A fuel cell is usually composed of a plurality of battery cells, each of which includes two electrodes (anode and cathode), which are separated by an electrolyte element, and are assembled in series with each other to form a fuel cell stack. By supplying each electrode with an appropriate reactant, that is, fuel for one electrode and oxidant for the other, an electrochemical reaction is achieved, thereby forming a potential difference between the electrodes, and thus generating electrical energy.

In order to supply reactants to each electrode, a specific interface element commonly referred to as a "bipolar plate" and provided on both sides of each individual cell is used. These bipolar plates are usually in the form of individual elements placed adjacent to the anode or cathode support. The bipolar plate is an important element of the fuel cell stack. During the operation of the fuel cell stack, the bipolar plates perform the following functions to maintain the optimal working state and service life of the fuel cell stack: (1) battery conductors, cathodes and anodes are formed on both sides of the plates, and one battery cell is connected in series To form a fuel cell stack; (2) Provide reaction gas (mass transfer) to the electrode through the flow channel; (3) Coordinate the management of water and heat to prevent leakage of cooling medium and reaction gas; (4) Membrane electrode assembly (MEA) ) Provide structural strength support.

The metal bipolar plate is formed by welding and bonding two cathode and anode veneers with a thickness of 0.07mm to 0.7mm. Cathode veneer has hydrogen, air, coolant inlet and outlet, grooved oxygen flow channel; anode veneer has hydrogen, air, coolant inlet and outlet, grooved hydrogen flow channel; because the board is very thin, laser welding is required, The two veneers are strictly overlapped and laminated. Because there are many grooves and holes on the veneer, it is difficult to press and welding is more difficult, and it is easily affected by the residual stress of stamping and welding, causing warpage. To reduce the flatness of the bipolar plate; the bonding method is very demanding for the adhesive, because the fuel cell will have a certain temperature during operation, and the metal plate in the process of thermal expansion and contraction, ordinary Viscose breaks easily.

These will cause the following problems: 1) the contact resistance of the membrane electrode and the bipolar plate, 2) the mechanical stability of the surface coating, which in turn affects the performance and life of the stack. Especially for large-area bipolar plates, in subsequent processes, such as surface treatment and assembly, if the strength of the bipolar plate is not enough, it is also easy to distort and deform.

Summary of the invention

The purpose of the present invention is to provide a fuel cell metal bipolar plate with low contact resistance, good electrical conductivity, convenient processing and easy assembly in order to overcome the above-mentioned defects in the prior art.

The object of the present invention can be achieved by the following technical solution: a fuel cell metal bipolar plate, characterized in that it includes a cathode plate and an anode plate formed by stamping a single-layer metal thin plate, and the cathode plate is stamped from the front The grooves form an oxidant flow channel, and the convex portions between adjacent grooves form an oxidant flow channel wall, and the punched grooves on the front surface of the anode plate constitute a fuel flow channel, and the convex portions between adjacent grooves A fuel flow channel wall is formed, a groove is formed on the back of the convex portions of the anode and cathode plates, the back and back of the cathode and anode plates are closely assembled, and the width of the groove and the ridge on the back of the two plates are narrow , Depth and direction are designed to directly constitute the coolant flow channel, the cathode plate and the anode plate are connected and distributed by the gasket frame sandwiched between the two plates and the bonding point between the two plates. After back-to-back fitting and close assembly, the back side is coupled to form a groove-to-groove or groove-to-ridge coolant flow channel, forming a bipolar plate composed of two single-layer thin plates to form three flow channels. That is, the design of the front oxidant flow channel or the fuel flow channel on the single-layer metal sheet needs to consider the design of the cooling channel on the back, and a series of parallel protrusions are stamped on the front of the single-layer metal sheet. The groove is used as a flow channel, and the front side is a protrusion, and the corresponding reverse side is a groove. The front grooves of the cathode and anode plates are used as an oxidant flow channel and a fuel flow channel, respectively. Groove, the grooves on the back of the two plates face each other, and the groove openings are connected to form a coolant flow channel, while the front face is the groove and the corresponding back face is the protrusion (ie ridge), the back of the two plates is the protrusion (ie ridge) Laminate together for bonding or welding. A large number of ridge-to-ridge conditions are likely to form on the back of the areas where the fluid inlet and outlet, the flow channel is bent or staggered in the cathode and anode plates described above, resulting in blockage of the coolant flow channel. Therefore, it must be considered when designing the front flow channel To the problem of the back flow channel, when two plates are combined back to back, at least one side (the back side of the cathode plate or the back side of the anode plate) is a groove structure to ensure the smooth flow of the entire coolant flow path, that is, in these areas, the ridge or groove The widths are unequal. To avoid clogging the coolant flow channel, the groove width or ridge width of at least one of the surfaces can be elongated.

The back surface of the cathode plate and the back surface of the anode plate are back-to-back tightly assembled. The tightly assembled can be distributed dot matrix bonding or distributed dot matrix welding. The grooves formed on the back of the two plates due to the convex front are relatively combined As a whole, the whole coolant flow channel is formed together; the top area of the coolant flow channel wall on the back of the two plates is correspondingly attached and assembled back to back, which can effectively reduce the contact resistance between the two plates and form two single-layer thin plates A well-conducting bipolar plate that constitutes a compact structure of three flow channels.

The middle area of the front surface of the cathode plate and the anode plate is the reaction area, and the periphery is the sealing area. The sealing area of the bipolar plate is flat except for the drainage groove. There is no sealing groove. The surface quality of the sealing area can be determined according to the sealing material. Choose different to make polished surface, rough surface and rubberized surface. The front and back surfaces of the cathode and anode plates have conductive anticorrosive coatings. The coating may be sprayed before or after stamping. The coating material may be metal or non-metal.

The bipolar plate is provided with an oxidant inlet, an oxidant drainage groove, an oxidant outlet, a fuel inlet, a fuel drainage groove, a fuel outlet, a cooling fluid inlet, a cooling fluid drainage groove, and a cooling fluid outlet, and the cathode plate is provided with a front face An oxidant drainage groove and an oxidant flow channel connecting the oxidant inlet and the oxidant outlet, a fuel drainage groove and a fuel flow channel connecting the fuel inlet and the fuel outlet on the front of the anode plate, the cathode plate and the anode A cooling fluid drainage groove and a cooling fluid flow channel connecting the cooling fluid inlet and the cooling fluid outlet are provided in the interlayer laminated on the back of the board.

The periphery of the cathode plate and anode plate is a sealing area. The front sealing area of the cathode plate is provided with a gasket a, the front sealing area of the anode plate is provided with a gasket b, and the interlayer sealing area of the cathode plate and anode plate is provided with a gasket frame On both sides of the gasket frame, the cathode plate and the anode plate are sealed and connected into a bipolar plate by means of adhesive bonding or welding.

The material of the gasket frame is silicone, PP or the same metal as the metal bipolar plate. When the bipolar plate expands and contracts, the thermal stress can be eliminated, so that even if the adhesive on both sides is an ordinary adhesive, it will not cause the adhesive to break due to excessive thermal stress.

After the cathode plate and the anode plate are superimposed, a coolant flow field is formed in the middle, and a frame-shaped cavity is formed around the coolant flow field, and the liner is filled in the frame-shaped cavity to avoid excessive use To avoid the problem of difficult selection of adhesive. The adhesive can be selected from conductive adhesive or non-conductive adhesive, and the material that can be selected for the backing plate can eliminate thermal stress.

The gasket frame has a square frame shape, and three inlets and three outlets corresponding to the cathode plate and the anode plate are provided at both ends, wherein a cooling fluid drainage groove is also provided inside the coolant inlet and outlet of the gasket frame The cooling fluid drainage groove can be made of porous material or corrugated plate with a certain thickness. The cooling fluid enters the cooling fluid flow path from the cooling fluid inlet on the gasket frame through the cooling fluid drainage groove, and then drains the cooling fluid from the other side. The tank enters the coolant outlet and flows out.

At least one sealant groove is provided on both sides of the gasket frame, on the one hand, it can prevent the adhesive from overflowing when the bipolar plate is pressed, on the other hand, it can strengthen the adhesive capacity, and apply adhesive on both sides of the gasket frame. The adhesive presses the cathode and anode plates on both sides of the gasket frame to form a bipolar plate.

The cathode plate and the anode plate are not provided with sealing grooves on both sides, and are sealed by the gasket frame and the gasket. The gasket frame and the gasket are both square frame-shaped structures, which are pressed onto the intermediate sandwich of the bipolar plate and the sealing area on both sides.

Compared with the prior art, the present invention has the following beneficial effects:

1. The flow channels (grooves) and flow channel walls (ridges) on the positive and negative sides of the cathode and anode plates are coupled (topological) design, while ensuring that the flow space on the positive and negative sides of the polar plate is smooth from the inlet to the outlet, and the fluid The flow distribution in the reaction zone is uniform.

2. There is no sealing groove on both sides of the cathode plate and anode plate, on the one hand, saving the grooving process, on the other hand, reducing the difficulty of the subsequent process, because the sealant is not coated in the sealing groove, but coated on both sides of the gasket frame The coating area is large, the operation is convenient, and there is no glue overflow, and the coating surface is enlarged. When the bipolar plate is pressed, it is a plane-to-plane pressing, it will not be displaced and deformed, and the bonding is more firm.

3. The channel groove depths of hydrogen and air/oxygen are different or the same, and the structure of the present invention can be adapted to many bipolar plate structures;

4. The cooling fluid flow field space can be directly composed of stamped cathode and anode plates back to back, with no filler material in the middle, and the design of the gasket frame only fills the cathode and anode plates due to the design of the protrusions and grooves The surrounding cavity structure is simple and lightweight, which eliminates thermal stress and reduces the difficulty of bonding the bipolar plates.

4. In the present invention, two single-layer metal thin plates are punched to form three flow channels, which make full use of the coupling of the grooves on the back of the Yin and Yang plates to form an overall coolant flow channel, which is simply sealed by a frame without the traditional sealing groove. There is no additional plate between the two plates to increase the height of the bipolar plate, and the only gasket frame sandwiched between the two plates is only filled in the frame cavity generated after the two plates are stamped, so the bipolar plate can be made very thin.

BRIEF DESCRIPTION

Figure 1 is an exploded view of the bipolar plate;

FIG. 2 is a schematic structural view of one side of a cathode plate of a bipolar plate;

Figure 3 is a schematic diagram of the structure after the bipolar plates are bonded;

4 is a schematic diagram of the assembly structure of the bipolar plate and the membrane electrode;

5 is a schematic diagram of the structure of the first type bipolar plate cooling fluid inlet and outlet;

Figure 6 is a schematic diagram of the structure of the second type of bipolar plate cooling fluid inlet and outlet;

7 is a schematic cross-sectional view of the three fluid inlet and outlet frames and the drainage groove of the bipolar plate;

8 is a schematic diagram of the partial structure of the third type of bipolar plate cooling fluid inlet and outlet;

9 is a partial side view of the bipolar plate;

10 is a schematic diagram of the partial structure of the fourth bipolar plate cooling fluid inlet and outlet;

11 is a partial cross-sectional view of a bipolar plate showing the overlapping and interleaving of flow channels and flow channel walls;

FIG. 12 illustrates a schematic diagram of a reaction zone and a distribution lattice using a cathode plate as a typical plate example.

detailed description

The present invention will be described in detail below with reference to the drawings and specific embodiments.

Example 1

As shown in FIG. 1, it is an exploded view of a metal bipolar plate, including a sealing pad 7, a cathode plate 1, a gasket frame 2, an anode plate 3 and a sealing pad 8 arranged in this order. The cathode plate 1 and the anode plate 3 are not provided with sealing grooves, and are sealed by the sealing pad 7, the sealing pad 8 and the gasket frame 2. The gasket a7 and the gasket b8 have a square frame shape. When the bipolar plate and the membrane electrode are assembled, they are sealed by a gasket.

As shown in FIG. 2, it is a schematic diagram of the planar structure of the cathode plate, which is provided with three inlets and three outlets: an oxidant inlet 9, an oxidant drain 6, an oxidant outlet 12, a fuel inlet 11, a fuel drain 4, a fuel outlet 14, and a cooling liquid An inlet 10, a cooling fluid drainage groove 5, and a cooling fluid outlet 13, an oxidant flow channel 16 connecting the oxidant inlet 9 and the oxidant outlet 12 on the front of the cathode plate 1, and an oxidant drainage at the oxidant inlet and outlet Groove 6, a fuel flow channel 18 connecting the fuel inlet 11 and the fuel outlet 14 is provided on the front of the anode plate 3, and a coolant inlet is provided in the interlayer attached to the back of the cathode plate 1 and the anode plate 3 10 and the coolant drain groove 5 and coolant channel 17 of the coolant outlet 13. And the connection between the oxidant inlet 9 and the oxidant outlet 12 and the oxidant flow channel 16 is the fuel drainage groove 4.

As shown in FIG. 3, a cathode plate 1 and an anode plate 3 formed by stamping a single-layer metal thin plate, the grooves punched on the front surface of the cathode plate 1 constitute an oxidant flow channel 16, and the convex grooves between adjacent grooves The oxidant flow channel wall is partly formed, the punched groove on the front of the anode plate 3 constitutes the fuel flow channel 18, and the raised portion between adjacent grooves forms the fuel flow channel wall. The cathode plate 1 and the anode The back of the plate 3 is close to each other, the oxidant flow channel 16 and the bottom of the fuel flow channel 18 are close to each other, the oxidant flow channel wall and the fuel flow channel wall are convex outward, and the inner groove is coupled to form a cooling liquid flow Road 17. The front grooves of the cathode plate 1 and the anode plate 3 are used as the oxidant flow path and the fuel flow path, respectively. The back surface corresponding to the front projection is the groove, the grooves on the back of the two plates are opposite, and the groove openings are connected to form the coolant flow path. The front side is the groove and the corresponding back side is the bump. The bumps on the back of the two boards are bonded together. In addition to the surrounding sealing area and the dotted frame 24, the bonding area can also be distributed dot matrix 25 bonding It can also be assembled by distributing dot matrix 25 (see FIG. 12, the middle area of the front surface of the cathode plate 1 and the anode plate 3 is the reaction area, that is, the dashed frame 24, and the front and back sides of the periphery are the sealing area, the dashed frame 24 Outer), the grooves formed on the back of the two plates due to the front protrusions are relatively combined together to form an overall coolant flow channel 17; the top areas of the walls of the coolant flow channels on the back of the two plates are correspondingly attached and assembled closely back to back, you can Effectively reduce the contact resistance between the two plates, and form a well-conducted bipolar plate with a compact structure of three flow channels formed by two single-layer thin plates.

The cathode plate 1 and the anode plate 3 are stacked back-to-back. The groove on the anode plate 1 fits with the groove on the cathode plate 3. The protrusion on the anode plate 1 is opposite to the protrusion on the cathode plate 3. A cooling fluid flow field 17 is formed, and a frame-shaped cavity is formed on the periphery, the thickness of the frame-shaped cavity is the same as the thickness of the cooling fluid flow field 17, or according to the depth of the oxidant flow channel 16 and the fuel flow channel 18 After adding the thickness of the two plate materials, the gasket frame 2 is filled in the frame-shaped cavity. The periphery of the cathode plate 1 and the anode plate 3 is a sealing area, that is, the area outside the dotted frame 24. The front sealing area of the cathode plate 1 is provided with a sealing pad a7, and the anode sealing plate 3 is provided with a sealing pad b8. The interlayer sealing area on the back of the plate 1 and the anode plate 3 is provided with a gasket frame 2 on both sides of the gasket frame 2 by means of adhesive bonding or welding (in this embodiment, adhesive bonding) ), the cathode plate 1 and the anode plate 3 are sealed and connected into a bipolar plate. Except for the drainage groove, the sealing area of the bipolar plate is flat and has no sealing groove. The surface quality of the sealing area can be made into a polished surface, a rough surface and a glue according to the selection of the sealing material sealing pad a7 and sealing pad b8. surface. The front and back surfaces of the cathode and anode plates have conductive anticorrosive coatings. The coating is sprayed before stamping. The coating material may be conductive anticorrosive metal materials.

At least one sealant groove 21 is provided on each side of the gasket frame 2, an adhesive 15 is coated on both sides of the gasket frame 2, and the cathode plate 1 and the anode plate 3 are pressed on both sides of the gasket frame 2 To form a bipolar plate. Both sides of the gasket frame 2 are provided with sealant grooves, on the one hand, it can prevent the adhesive from overflowing when the bipolar plate is pressed, and on the other hand, it can strengthen the adhesion ability. The gasket frame 2 has a square frame shape, and is provided with three inlets and three outlets corresponding to the cathode plate 1 and the anode plate 3 at both ends, wherein a plurality of parallel cooling fluid drainage grooves 5 are provided inside the cooling fluid inlet and outlet , More conducive to the introduction of cooling fluid into the cooling fluid flow field. As shown in FIG. 7, it is a cross-sectional view of the frame of the bipolar plate. The cathode plate 1 is provided with an oxidant drainage groove 6, the anode plate 3 is provided with a fuel drainage groove 4, and a staggered cooling fluid drainage groove is formed on the gasket frame 2 5.

As shown in FIG. 4, a membrane electrode is sandwiched between two bipolar plates. The membrane electrode includes a proton exchange membrane 20 in the middle, a catalyst layer and a gas diffusion layer 19 disposed on both sides of the membrane electrode, wherein the catalyst layer and the gas diffusion layer 19 The area is the same as the area of the flow field on the cathode and anode plates. The connection frame is provided on both sides of the membrane electrode. The thickness of the connection frame and the middle of the membrane electrode is less than the thickness of the middle of the membrane electrode. The thickness of b8 is the same, so that the assembly will not be uneven due to the difference in thickness. The structure of the membrane electrode can adopt the structure in the invention patent ZL2014107077112.

Example 2

As shown in FIG. 5, the coolant drainage groove 5 on the inside of the coolant inlet and outlet of the gasket frame 2 uses a porous material 22 corresponding to the thickness of the gasket frame, and the coolant passes through the porous from the coolant inlet 10 on the gasket frame 2 The material 22 enters the coolant flow channel 17 and then enters the coolant outlet 13 from the porous material on the other side and flows out.

The rest is the same as in Example 1.

Example 3

As shown in FIG. 6, the coolant drainage groove 5 on the inner side of the coolant inlet and outlet of the gasket frame 2 is composed of a corrugated plate 23 corresponding to the thickness of the gasket frame, and the coolant passes through the coolant inlet 10 on the gasket frame 2 The corrugated plate 23 enters the coolant flow channel 17 and then enters the coolant outlet 13 from the porous material on the other side and flows out. The front and back surfaces of the cathode and anode plates have conductive anticorrosive coatings, the coating is sprayed after stamping, and the coating material is a conductive anticorrosive non-metallic material.

余同同实施例1。 The same as in Example 1.

Example 4

When designing the front oxidant flow channel or the fuel flow channel on the single-layer metal sheet, you need to consider the design of the cooling channel on the back. A parallel protrusion is punched out on the front of the single-layer metal sheet, and the recess between adjacent protrusions The groove serves as a flow channel, and the front surface is a protrusion, and the corresponding reverse surface is a groove. The front grooves of the cathode plate 1 and the anode plate 3 serve as the oxidant flow channel 16 and the fuel flow channel 18, respectively, and the back ridges of the cathode plate 1 and the anode plate 3 The ridges and the grooves are bonded to each other. The cathode plate 1 front oxidant flow channel 16 is attached to the anode plate 3 front fuel flow channel 18 bottom. The front side of the convex (ie ridge) corresponding to the back is a groove, and the back of the two plates is groove Opposite to each other, the openings of the grooves are connected to form the coolant flow channel 17, while the front side is the groove and the corresponding back side is the protrusion (i.e., ridge). Or welding, as shown in Figure 9. Large areas of ridge-to-ridge conditions are likely to be formed on the back of the fluid inlet and outlet, flow channel bends or staggered areas on the cathode plate 1 and anode plate 3, resulting in blockage of the coolant flow path. Therefore, when designing the front flow path The problem of the back flow channel must be considered. At least one side (the back side of the cathode plate or the back side of the anode plate) of the two plates combined back to back is a groove structure. As shown in FIG. 8, the oxidant drainage groove 6 at the fluid inlet and outlet of the cathode plate 1 is uneven Groove, the anode plate 3 corresponding to it is an elongated convex surface, and another type of cooling fluid drainage groove 5A with a concave and convex side and a flat plate side is formed between the two; as shown in FIG. 10, the fluid outlet at the cathode plate 1 The place is an elongated convex surface (that is, the height of the anode plate is the same as the height of the side walls on both sides of the oxidant channel), and the corresponding anode plate 3 fluid in and out of the fuel drainage groove 4 is a concave and convex groove, and a third side is formed between the two The flat cooling fluid drainage groove 5B on the concave and convex side ensures smooth flow of the entire cooling fluid flow path.

At least one surface on the back side of the area where the fluid inlet and outlet, the flow channel is bent or staggered on the cathode plate 1 and the anode plate 3 is a groove structure to ensure the smoothness of the entire cooling liquid flow channel 17. As shown in Figure 11, staggered cooling fluid drainage grooves 5A and cooling fluid drainage grooves 5B are formed at the back of the fluid inlet and outlet, that is to say, the design of the grooves and ridges on the bipolar plate is not static, but complementary, the same Different flow channels can be designed on the board, the purpose is that the flow channels on the front of each plate are unobstructed while satisfying the smooth flow of the coolant channels formed on the back.

Example 5

As shown in FIG. 12, it is a schematic diagram of the back structure of the cathode plate, in which the convex parts of the cathode plate front form grooves on the back, and the groove parts on the front form the ridges between the coolant channels of the back side. The same is true for the back of the anode plate. When the two plates are back to back, the connection ridges 25 are selected on the two contact surfaces of the back ridges. The two plates are welded through the connection distribution points 25 to form a bipolar plate. (Adhesion can also be used, and the adhesive distribution dot matrix 25 is located on the ridges on the back of the two boards). The number of points of the distribution lattice 25 can be selected according to the structural stability and the electrical conductivity of the contact surface, which can be more or less.

The middle area of the front surface of the cathode plate and the anode plate is the reaction area, that is, the reaction area is within the dotted frame 24, and the corresponding back surface is the main cooling flow field area. The rest is the same as in Example 1.

Claims

A fuel cell metal bipolar plate, characterized in that it includes a cathode plate (1) and an anode plate (3) formed by stamping a single-layer metal thin plate, and the cathode plate (1) is formed by stamping a groove on the front The oxidant flow channel (16), the convex part between the adjacent grooves form the oxidant flow channel wall, and the punched groove on the front of the anode plate (3) constitutes the fuel flow channel (18), the adjacent concave The protruding parts between the grooves form the wall of the fuel flow channel, the front convex parts of the anode plate (1) and the cathode plate (3) respectively form grooves on the back, and the groove parts on the front form the back coolant The ridges between the flow channels, the grooves on the back of the two plates and the ridges are coupled to form a groove-to-groove or groove-to-ridge coolant flow channel (17), which constitutes a double layer consisting of two single-layer thin plates and three flow channels. Polar plate.
A fuel cell metal bipolar plate according to claim 1, characterized in that the cathode plate (1) and the anode plate (3) have a protrusion formed on the back surface of the front part of the groove, and the two plates are tightly back to back For assembly, the raised part on the back is bonded in whole or in part by the connection distribution dot matrix (25), or the connection distribution dot matrix (25) is welded and combined into one.
A fuel cell metal bipolar plate according to claim 1, characterized in that there is at least one back side of the area where the fluid inlet and outlet, the flow channel is bent or staggered on the cathode plate (1) and anode plate (3) The surface is a groove structure to ensure the smoothness of the entire coolant flow channel (17).
The metal bipolar plate of a fuel cell according to claim 1, characterized in that the intermediate area on the front of each of the cathode plate (1) and the anode plate (3) is the reaction area, that is, within the dotted frame (24) , The front and back sides of the periphery are sealing areas, that is, the dotted frame (24), the sealing area of the bipolar plate is flat except for the drainage groove, and there is no sealing groove. The surface quality of the sealing area is polished, rough or painted Glue surface.
A fuel cell metal bipolar plate according to claim 1, characterized in that the front and back surfaces of the cathode plate (1) and anode plate (3) have conductive anticorrosive coatings, the The coating may be sprayed before or after stamping, and the coating material may be metal or non-metal.
The fuel cell metal bipolar plate according to claim 1, characterized in that the bipolar plate is provided with an oxidant inlet (9), an oxidant drainage groove (6), an oxidant outlet (12), a fuel inlet (11), fuel drain groove (4), fuel outlet (14), coolant inlet (10), coolant drain groove (5), coolant outlet (13), the cathode plate (1) is provided on the front An oxidant drainage channel (6) and an oxidant flow channel (16) connecting the oxidant inlet (9) and the oxidant outlet (12), and the anode plate (3) is provided with a fuel inlet (11) and A fuel drainage groove (4) and a fuel flow channel (18) of the fuel outlet (14), and a cooling fluid inlet (10) and a cooling fluid inlet (10) are provided in the interlayer attached to the back of the cathode plate (1) and anode plate (3) The coolant drain groove (5) and the coolant flow channel (17) of the coolant outlet (13).
The metal bipolar plate of a fuel cell according to claim 1, wherein the cathode plate (1) and the anode plate (3) are superimposed to form a coolant flow field in the middle, and the coolant flow field A frame-shaped cavity is formed on the periphery, and the frame-shaped cavity is filled with a gasket frame (2).
The fuel cell metal bipolar plate according to claim 1, wherein the periphery of the cathode plate (1) and the anode plate (3), that is, outside the dotted frame (24) is a sealed area, The front sealing area of the cathode plate (1) is provided with a gasket a (7), the front sealing area of the anode plate (3) is provided with a gasket b (8), and the cathode plate (1) and anode plate (3) are provided with a sandwich sealing area on the back There is a gasket frame (2), and the two sides of the gasket frame (2) are sealed and connected into a bipolar plate by means of adhesive bonding or welding, and the cathode plate (1) and the anode plate (3) are sealed. Further, at least one sealant groove (21) is provided on each side of the gasket frame (2), an adhesive (15) is coated on both sides of the gasket frame (2), and the cathode plate (1) and The anode plate (3) is pressed on both sides of the gasket frame (2) to form a bipolar plate.
The fuel cell metal bipolar plate according to claim 6, characterized in that the material of the gasket frame (2) is silicone, PP or the same metal as the metal bipolar plate.
A fuel cell metal bipolar plate according to claim 6, characterized in that the gasket frame (2) has a square frame shape, and is provided with a cathode plate (1) and an anode plate ( 3) Corresponding three inlets and three outlets, wherein a cooling fluid drainage groove (5) is provided inside the cooling fluid inlet and outlet on the gasket frame (2), and the cooling fluid drainage groove (5) can be made of a porous material with a certain thickness ( 22) or corrugated plate (23), the cooling liquid enters the cooling liquid flow channel (17) from the cooling liquid inlet (10) on the gasket frame (2) through the cooling fluid drainage groove (5), and then cools from the other side The fluid drainage groove (5) enters the coolant outlet (13) and flows out.